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sediments that were probably being transported from upstream during the higher flows in 1993. The 050's of both samples are similar (- 69mm). The gradation of MH10 is bimodal and this Wolman Count represents deposition of sand over the coarser gravels and cobbles. The 050 is about 56 mm, but about 35 percent of the gradation is sand sized which is in contrast to MH7 and MH8 where less than 5 percent of the gradation is sand sized. With the exception of MH10 which represents two different populations, and MH1 and MH5 which are the products of flow separation, the surface sediments represent pavements since the sorting values (Os) lie between 1.7 and 2. MH11 was conducted on the left bank of the right chute channel between X5 5 and X5 6. The sediments that form the bank appeared to be finer than those at equivalent locations farther upstream, but there was little evidence of recent transport since most of the individual clasts were varnished. Most of the clasts were embedded in a matrix of finer muds that was probably deposited during flow recession and subsequently sun baked (Harvey et aI., 1993). The 050 was 57 mm which is somewhat finer than that at MH7 (68mm). It appears that. the mud matrix is providing a measure of cohesion to the otherwise granular sediments. The characteristics of the mud matrix are probably very similar to that of the flocculated mud sample collected at the edge of the water at X5 4. Ninety fIVe percent of the sample is finer than sand (<O.062mm; silt and clay), and 80 percent is finer than silt (<O.0047mm) [Appendix A]. The subsurface samples, 52, 53, 54, and 56 are representative of the bed material load gradations (Parker et aI., 1982) at the various locations around the bar. The sorting values (Os) for these samples range from 4.3 to 18.9 (Table 3.1). The coarsest gradation is located at the head of the bar (53) [X5 12] as is to be expected. The 084 for the sample is about 154mm. Downstream fining is seen at 54 (084 = 132mm) [X59] and 56 (084 = 65mm) [- X55]. 5ample 55 was collected from the base of a pit dug into the slipface of the bar at X5 9. The basal part of the bar was composed of clean sand (050 = O.4mm) that was overlain by steeply dipping sand and gravel foresets. Pits 1, 2, and 3 (Figure 3.1) had very similar stratigraphy. The surface sediments represent a pavement that overlies massive, poIymodal very poorly sorted matrix supported conglomerate. In each of the pits, but at different depths there is at least one buried pavement layer underlying the matrix supported conglomerate. No buried pavement layers were observed at Pit 4, probably because this location on the bar represents a transition zone that has sediment deposited both as a result of backwater conditions downstream, but also as a result of flow expansion upstream. The sediments in the pit were uniformly massive, poorly sorted matrix supported conglomerates. Where present, the buried pavement layers and the overlying sediments probably represent individual bar building events. Pit 5 represents a slipface where sediments are transported over the upper bar surface and cascade into the deeper flow in the right chute channel. 3.8 Resource Consultants & Engineers, Inc.